Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Numerator:
Income from continuing operations	$ 15,898	$ 203,623
Income (loss) from discontinued operations	104	(15)
NET INCOME	16,002	203,608
Adjustment for basic earnings per share:
Earnings allocated to unvested shareholders	(260)	(1,258)
Numerator for basic earnings per share:
From continuing operations	15,638	202,365
Income (loss) from discontinued operations	104	(15)
Net income (loss) attributable to parent, basic	15,742	202,350
Adjustment for diluted earnings per share:
Effect of reallocating undistributed earnings of unvested shareholders		6
Numerator for diluted earnings per share:
From continuing operations	15,638	202,371
Income (loss) from discontinued operations	104	(15)
Net income (loss) attributable to parent, diluted	$ 15,742	$ 202,356
Denominator:
Denominator for basic earnings per share - weighted-average shares	107,852	107,973
Effect of dilutive shares from stock options and restricted stock (in shares)	557	870
Denominator for diluted earnings per share - adjusted weighted-average shares	108,409	108,843
Basic earnings per common share:
Income from continuing operations (in dollars per share)	$ 0.15	$ 1.87
Net income (in dollars per share)	0.15	1.87
Diluted earnings per common share:
Income from continuing operations (in dollars per share)	0.15	1.86
Net income (in dollars per share)	$ 0.15	$ 1.86
Outstanding equity awards
Shares excluded from calculation of diluted earnings per share	1,899	669
Weighted-average price per share (in dollars per share)	$ 63.66	$ 72.87